The following relates to systems and methods for providing services to an electric power grid. For example, an ancillary system may provide a load whose electric power draw can be adjusted in order to provide capacity for use in frequency regulation of the electric power grid. The ancillary system may additionally or alternatively provide source capacity whose electrical power supplied to the electric grid can be adjusted in order to provide capacity for use in frequency regulation of the electric power grid. By way of illustrative example, it is known to provide ancillary power generators to provide excess source capacity, and/or flywheels or the like to provide excess load.